Java递归查询树结构：如何返回包含完整路径的树形查询结果？

java如何递归返回树结构的查询结果？

问题详情：

需要实现根据给定名称（如“秦朗”）查询一个树形数据结构并返回结果，其中结果以一条链路表示，如“三国-曹操-秦朗”。

代码：

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public class people {

    private list children;
    private string name;

    // ... getter and setter methods omitted
}

public static void main(string[] args) {
    // ... code to create and populate the tree structure
}

public static list query(people people, string name) {
    list result = new arraylist<>();

    // check if the current node matches the name
    if(people.getname().contains(name)) {
        return arrays.aslist(people);
    } else {
        // if not, recurse into the children
        if(people.getchildren() != null) {
            for (people p : people.getchildren()) {
                result.addall(query(p, name));
            }
        }
    }

    return result;
}

问题：

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上述代码会返回该名称的所有匹配项，但不会构建包含所有父节点的树结构。

解决方案：

要构建包含所有父节点的树，可以使用以下优化后的代码：

import com.alibaba.fastjson2.JSON;
import lombok.Data;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

@Data
public class PeopleVO {
    private Integer id;
    private String peopleName;
    private Integer parentId;
    List children = new ArrayList<>();

    // ... other methods omitted

    // Main method
    public static void main(String[] args) {
        // ... code to create and populate the tree structure

        // Search for "孙坚" and return the results as a tree
        List searchResult = searchPeople(tree, "孙坚");
        List resultTree = createTree2(searchResult);
        System.out.println(JSON.toJSONString(resultTree));

        // Expected output: [{"children":[{"id":3,"parentId":0,"peopleName":"孙坚"}],"id":0,"parentId":-1,"peopleName":"三国"}]
    }

    // Create a tree structure from a list of nodes
    private static List createTree(List lists, int pid) {
        // ... implementation omitted
    }

    // Search for a person in the tree structure
    private static List searchPeople(List tree, String name) {
        // ... implementation omitted
    }

    // Assemble the result nodes into a tree structure
    private static List createTree2(List nodeList) {
        // ... implementation omitted
    }
}

优势：

• 创建了一个包含所有父节点的树结构。
• 使用了fastjson库将树结构转换为json格式。
• 优化了代码以提高性能。